CVE-2022-39293

 

Published at: - 13-10-2022 09:15

Last modified: - 18-10-2022 10:30

Total changes: - 2

Description

Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in [_ux_host_class_pima_read](https://github.com/azure-rtos/usbx/blob/master/common/usbx_host_classes/src/ux_host_class_pima_read.c), there is data length from device response, returned in the very first packet, and read by [L165 code](https://github.com/azure-rtos/usbx/blob/082fd9db09a3669eca3358f10b8837a5c1635c0b/common/usbx_host_classes/src/ux_host_class_pima_read.c#L165), as header_length. Then in [L178 code](https://github.com/azure-rtos/usbx/blob/082fd9db09a3669eca3358f10b8837a5c1635c0b/common/usbx_host_classes/src/ux_host_class_pima_read.c#L178), there is a “if� branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length� where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then [L182 code](https://github.com/azure-rtos/usbx/blob/082fd9db09a3669eca3358f10b8837a5c1635c0b/common/usbx_host_classes/src/ux_host_class_pima_read.c#L182) the calculation of data_length is also overflow, this way the later [while loop start from L192](https://github.com/azure-rtos/usbx/blob/082fd9db09a3669eca3358f10b8837a5c1635c0b/common/usbx_host_classes/src/ux_host_class_pima_read.c#L192) can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release [6.1.12](https://github.com/azure-rtos/usbx/releases/tag/v6.1.12_rel). The following can be used as a workaround: Add check of `header_length`: 1. It must be greater than `UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE`. 1. It should be greater or equal to the current returned data length (`transfer_request -> ux_transfer_request_actual_length`).

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

 

Verification logic

 

Reference

• https://github.com/azure-rtos/usbx/releases/tag/v6.1.12_rel
• https://github.com/azure-rtos/usbx/security/advisories/GHSA-gg76-h537-xq48

 

Keywords

NVD

 

CVE-2022-39293

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures